Strolling down the central shopping precinct in Keighley on a sunny afternoon this week, two brothers stopped to promise the UK Independence party their votes. "No one else is ever getting mine now," said former Liberal Democrat supporter Brian Nicholson, 69, as his brother David, 70, previously a Tory, nodded in vigorous approval. "They're the only ones who say what people on the streets are actually thinking," said Brian. Which is? "That there are too many immigrants."

The fact they had just pledged allegiance to a man born in Pakistan did not strike them as at all ironic. "He's behaving the same way we are," said David.

He glanced over at Amjad Bashir, second on Ukip's list in Yorkshire for the European elections, as he sought support outside BHS in a light suit and striped tie. "He's wearing the same thing we are – not those pyjamas. That sort of thing makes me uncomfortable. I don't like the burqa either."

If all goes according to plan for Ukip next Thursday, Bashir, 61 – known as Peter to British colleagues in the restaurant trade – will soon take up a seat in the European parliament. That is despite him finding himself embroiled in a controversy over employing illegal immigrants at one of his family's curry houses.

Assuming Yorkshire's Eurosceptic voters are not put off by the revelation that his sons' Zouk restaurant in Manchester was fined last year after four "immigration offenders" with fake papers were found on the payroll, Bashir could well be one of six Ukip MEPs representing Yorkshire and North Lincolnshire. The party officially has no MEPs in the region, but only because it kicked out Godfrey Bloom last year following the "bongo bongo land" race row. (Independent since his ejection, Bloom is not seeking re-election.)

A strong result in Yorkshire would suggest Ukip had really branched out from its heartland. "If they get three MEPs in Yorkshire, it probably means they will have come top of the poll across the country," said Anthony Wells, a polling expert from YouGov. He thinks Ukip will also win two or even three seats in the north-west and one in the north-east.

"Winning big in the north will have a big significance, and I'll tell you why," said Bashir over a cheese and tomato toastie in Keighley. "We've been accused of being a fringe party of the Conservatives and of being very successful in the south as opposed to the north. We've had a presence in the north: one MEP in Yorkshire, one in the north-west [deputy leader Paul Nuttall], none in the north-east. But we've been stronger further south.

Ukip MEP candidate Amjad Bashir (centre) campaigns in Keighley despite being embroiled in a controversy over employing illegal immigrants at one of his family's curry houses. Photograph: Christopher Thomond for the Guardian Christopher Thomond/Guardian

"It's important we do well in the north as well... to send a very strong message both to Europe and our national leadership that what we are saying is resonating with the people. Nationally, we're hoping for 25-plus MEPs out of 72 in the 12 regions – then we'll be the largest group."

Two of the four seats Ukip has the best chance of winning in next year's general election are in Bashir's constituency, according to Robert Ford and Matthew Goodwin in their book, Revolt on the Right. These are in Grimsby and Scunthorpe, where Ukip needs a swing of less than 20 points.

Yorkshire's electoral possibilities are not lost on Nigel Farage, Ukip's irrepressible leader. Last month he began his nationwide tour in Sheffield, and he campaigned heavily in recent byelections in Rotherham and Barnsley, where the party was runner-up to Labour.

After the disastrous finale to Bloom's Ukip career, it initially seemed the party had been rather more careful in their selections this time around. Number one on their list in Yorkshire is Jane Collins, the party's regional organiser – a former aide to Bloom and a recent survivor of breast cancer who contested both aforementioned byelections with aplomb.

Until his appearance on the Times front page this week, Bashir may have seemed a canny choice too. A wealthy businessman who has donated more than £10,000 to the party, he was born in Jhelum in the Punjab in 1952 but moved to Bradford aged eight when his dad got a job in the mills.

Fifty-three years on, he has a broad Yorkshire accent but still speaks fluent Urdu: a boon in a constituency containing places such as Bradford, where 20% of the population are of Pakistani heritage. In Keighley on Wednesday he greeted two Asian ladies with a cheery "Assalamu alaikum!", before calling them "my loves" when it became apparent English was their native tongue. He launched right into an oblique defence of his party.

"They say Ukip is this, that and the other, but I wouldn't be in the party if they were racist, would I?"

He accepts that Ukip will likely hoover up votes which previously went to the far right British National party. Elected in Yorkshire as a British National Party candidate in 2010, MEP Andrew Brons is stepping down after falling out with the BNP leader, Nick Griffin.

Nonetheless, some of Bashir's voters' views must be hard to stomach: informed that one of his voters had just told the Guardian that they were voting for Ukip "because Enoch Powell was right," he failed to suppress a cringe before saying: "The world is full of people of different persuasions. What I think she was perhaps saying is that she is concerned about immigration." Meanwhile, at the Ukip stall, a young lad told campaigners they had his vote – "If there's no EDL (English Defence League) candidate on the list".

As Ukip's small business tsar – as well as occasional immigration spokesman – it was embarrassing, to say the least, when the Times article appeared.

Bashir subsequently maintained he had stepped down from the business a month before the raid on 1 June last year and told the Guardian he had never had a "hands-on role" in the curry house.

Yet in April this year he was shown in the kitchen at Zouk in a party political broadcast, where he complained that "EU regulations place a stranglehold on businesses and cost jobs." And it is curious that his resignation from the company was only electronically registered with Companies House two days after the restaurant was visited by immigration officials.

The Home Office said that seven men were arrested in the raid, and that three Pakistani men had now been deported for visa violations while three other men were still being investigated. It said the restaurant was fined. An eighth man, from Pakistan, who was also found working at Zouk and arrested at a later date, has also been removed from the UK.

Bashir said Zouk had inadvertently employed temporary workers with fake passports and visas. He blamed government bureaucracy for the legal breach, saying businesses were unfairly forced to do the job of the UK Border Agency. "This is a dereliction of duty on the part of the government. What I mean is, border control and immigration control is the role of the government. What's it got to do with businesses? Are we trained in immigration law?

"They are asking businesses to carry out their work, not just in immigration but almost everything – tax collection, VAT collection. All sorts of legislation has been put on businesses, which is not right. This is why I became a politician, to say this is the role of government, not business. Businesses are there to create jobs. They are there to make money for themselves and their employees."

Yet it is exactly this sort of controversy that deterred some voters in Keighley. "They are always in the news for bad things. I only ever hear of them in the negative," said Josh Irving, 29, an electrician. "I do agree that we should be separate from Europe, but I worry we will lose out on jobs and trade."

Cab driver Paul Atkinson, 52, was put off after the departure this week of another of Ukip's rising minority ethnic stars. Indian-born Sanya-Jeet Thandi quit the party on Tuesday, accusing it of "playing the race card".

"I don't think they can be trusted," said Atkinson. "If their own people are leaving them and accusing them of being racist then what does that tell you?"